Semiconductor device fabrication is a process used to create integrated circuits that are present in everyday electrical and electronic devices. The fabrication process is a multiple-step sequence of photolithographic and chemical processing steps during which electronic circuits are gradually created on a wafer composed of a semiconducting material.
The various processing steps fall into a number of categories including deposition, removal, patterning, and modification of electrical properties (i.e., doping). Chemical vapor deposition (CVD) is one of a number of commonly used processes for performing deposition processing steps. Typically, a CVD process involves exposing a wafer or substrate to one or more volatile precursors, which react and/or decompose on the wafer surface to produce a deposited layer. CVD processes are commonly used in semiconductor fabrication to form layers of polysilicon, silicon dioxide and silicon nitride.